A method, system, and computer usable program product for securing a data communication against attacks are provided in the illustrative embodiments. A segment in the data communication is received at a first application executing in a first data processing system. The segment is formed according to a data communication protocol and includes an option. The option includes a current clue and a next clue. The current clue is compared with a saved next clue, the saved next clue being a next clue in a previous segment. The segment is accepted as being a valid segment in the data communication if the current clue matches the saved next clue. A part of the segment is sent to a consumer application.